Generally, an automobile is used as a transportation means, and the purpose is to bring convenience to users. Nowadays, the relative importance of the automobile is gradually increasing as an essential necessity for social life as well as daily life beyond the level of the mere transportation means.
As described above, the number of automobiles in South Korea is continuously increasing and has already exceeded about 10 million, in line with the social development. Considering the number of the automobiles, South Korea can be regarded as a developed country. However, a shameful statistic is that the number of automobile accidents based on the population is the highest in the world. In particular, because a median barrier or a protective barrier at the side of a road (which will be hereinafter referred to as a protective barrier) is rarely installed on roads in South Korea, drivers always travel with a higher risk of being in an accident.
Meanwhile, protective barriers are classified into a fixed type, which is installed on the center line or at the side of the road, and a buried type, which is buried at the center line or at the side of the road. The fixed type includes concrete blocks, installed on the center line or at the side of the road. The fixed type is constructed by connecting the blocks one by one and then fixing them on the center line or at the side of the road using bolts.
However, the above-described fixed type of the protective barrier installed on the center line or the side of the road cannot absorb the impact from a car collision, but merely prevents intrusion of a car into the oncoming lanes or a car from leaving the road. Accordingly, the impact from a car collision is wholly transferred to the car, causing damage to the car in addition to injury or death.
For the buried type of the protective barrier, which is buried at the center line or at the side of the road, the following structure can be presented as an example. A pillar is buried at the center line or at the side of the road, and then a guide rail or a fence having a predetermined waveform is fixed to the pillar at both sides or one side of the pillar by using nuts and bolts. Then, a plurality of waste tires is installed at the pillar to reduce the impact from a car collision.
According to the above-described buried-type protective barrier buried at the center line or the side of the road, the impact from a car collision can be absorbed by the protective barrier and be dispersed to reduce the scale of the accident and to reduce injuries or deaths. However, the velocity of the car may not be reduced because of the rotational power of the waste tires, but instantly increased to induce deviation of the car from the driving lane. This problem may cause a secondary collision with a car traveling in an adjacent lane to generate a serious traffic accident.
In addition, since the structure of the protective barrier of the buried type at the center line or the side of the road is very complicated, the manufacturing cost may be increased and the assembly time of the components at the construction site may be lengthened. Particularly, when a car collision occurs at a place where the front car cannot be observed due to road conditions, such as a curved road or an uphill road, other cars might travel without recognizing the accident to induce a more serious accident.
In order to solve the above-described problem, the Applicant of the present invention filed Utility Model Application No. 2005-13826 on May 17, 2005 in the Korean Intellectual Property Office (KIPO) with the title of “Median Strip for Shock Absorber.” This utility model was registered on Jul. 28, 2005 as Utility Model No. 391872. According to this utility model, the impact absorbing body of the median strip for a shock absorber was manufactured by using a synthetic resin, and thus there was a problem in that the impact absorbing body typically broke into pieces due to the impact from a car collision.